Magneto



A. H. HYNDMAN.

MAGNETO.

APPLICATION FILED 1AN19,19l9.

Patented Jan. 17

SHEETS-SHEET 2.

ALEXANDER H. HYNDMAN, OFTCHICAGO, ILLINOIS.

MAGNETO.

Application filed January 9, 1919.

T 0 all @2 2 am it may concern Be it known that I, ALEXANDER H. HYND- rain, a'citizen of Canada, residing at Chicago, in the county of Cook, State of Illinois. have invented certain new and useful Improvements in Maguetos, or" which the following is a specification.

The present invention relates generally to magnetos of the oscillating armature type and more particularly to magnetos of this type which are used with internal combustion engines to supply the electric current for exploding the fuel charges in the engine cylinders. The principal object of the in vent-ion is to produce a magneto of the kind specified which shall be eiiicient and d rable in operation and at the same time economical to manufacture. Another object of the invention is to provide a novel construction which is readily adaptable to the production of either high or low tension machines. For a full understanding or" my invention referones should be had to the following detailed description taken in connection withtheaccompanying drawing, while the scope or the invention will be set forth in the appended claims.

In the said drawing, Fig. 1 is a side elevation of a low tension magneto constructed in accordance with my invention; Fig. 2 is a front elevation of the same; Fig. 3 is a bottom plan view of the same; Fig. 4c is a diagram illustrating said magneto in association with an engine cylinder and showing particularly the electric circuit; Fig. 5 is a side elevation of ahigh tension magneto constructed in accordance with my invention; Fig. 6 is front elevation of the same; Fig. 7 is a fragmentary view in side elevation illustrating the main armature and associated parts in depressed position; Fig. 8 is a bottom plan view of the high tension structure; and Fig. 9 is a diagram of the electrical circuits of the high tension ma chine. Throughout these views like characters refer to like parts.

Referring more particularly to the low tension machine, illustrated in Figs. 1' to a inclusive, 10 designates a permanent magnet which is preferably of horse-shoe shape. This magnet is secured to a suitable base 11 by a bolt 12 which passes through holes in said base and in a bar 13 which bridges the space between the arms of the magnet and bears against them at its outer ends, The nut 14 on the threaded end of Specification of Letters Patent.

Serial No. 270,260.

the bolt 12, when screwed down tightly against the bar 13, securely holds the parts in place, it being understood thatthe head of the bolt 12 engages the rear face of the base 11. The magnet 10 is composed of steel or other suitable magnetic material while the base 11 and the bar 13 are composed of brass or other suitable non-magnetic material.

The armature 15 consists of a bar 16 upon which the tightly fitting blocks or sleeves 17 and 18 are firmly secured. These blocks are in position to engage the pole faces of the magnet 10 and together with the intervening portion of the bar 16, complete the magnetic circuit between those poles. The bar 16 and the blocks 17 and 18 are composed or"- soft iron or other suitaole magnetic material. The armature 15 is guided in its to and fro movements by guiding members 26 and 21 of brass or other non-magnetic material which are secured to the base 11 by any suitable means, as for example by screws, such as the screw 22 shown in connection with the guide 20. Each of these members 20 and 21 is in the form of yoke with a central open portion, which provides space for the free movement of the bar 16. The depending portions of the guide 21 and the adjacent end oi the bar 16 are provided with holes for the passage of a pivot pin 23. About this pin as a center the armature 15 oscillates and it is guided in its oscillations by the dependingportions of the guide 20. It may be pointed out that the pin 23 need not be used but may be withdrawn from the structure and still the depending portions of the guide member 21 will suiiice to hold that end of the armature against displacement through all the to and fro movements of the opposite end. It will be observed that the magnetic flu): through the armature and the adjacent pole pieces will tend to hold the armature against displacement at this point. The opposite end of the bar 16 extends some distance beyond the magnet 10 and is to be positioned so as to be actuated by an oscillating member 24: which is given its oscillatory movement by the engine or other mechanism with which the magneto is to be used. This member 24 should be arranged to give a quick sharp blow to the end. of the bar 16 of the armature. Such a blow will force the bar 16 downward be tween the depending guiding portions of the Patented Jan. 1'7, 1922.

member 20. its return may be brought about wholly in response to the action of or its return may be assisted use of a return compression spring m-cor a lien the spring 25 and yoke 26 il te l.

29 is mounted upon that portion or the bar 16 which lies between the magnetic bloclrs 1'7 and 18. is indicated in the diagram of Fi 4:, one terminal of the coil 29 is grounded and the other is connected to insulated terminal 30 which constitutes one oi the sparking terminals in the cylinder 81 of an internal combustion engi e The other spa 1 'ng terminal 32 is 7 upon a reciprocating rod 33 which actuated by the tree end of the bar As the downward the conmechanically moved out of engagewith contact 30. As the free end or" the armature bar 16 moves upward a spring 30- 8d upo .ne rod acting between the enune o der and the sleeve 35 on the rod @rdinarily, the ground conneccoil 29 is by connecting one 35 --';crminaiof Lil coil to some portion otthe str cture which is grounded. In tie present instance connection is made with he burl i l tter is shown grounded at 36 the contact 32 is at electrically connected to th r; nl1 ground connection of th is indicated at 37. From these coni will be seen that a circuit may be tracer. from groi l 36 through a portion or 331 16. the dings of coil 29, conductor con acts 30 and 82, and engine cylinder 31 to ground at 37. it may be pointed out that the contact 30 which extends through the cylinder head is provided suitable r 4 tion shown at 39. From th' ciiption it will be seen that p f the a mature bar 16 is her blow by the oscillat- Inagnetic circuit which is ntervening portion of bar d and the number oi lines normally pass through the eady lessened by reason a movement of the free end circuit through the coil 29 and the sparking contacts 30 and 32. With this low tens1on acts between the under side of thetime when the current flowing magnetic attraction of the type of machine the downward movement of the armature bar 16 and the mechanical opening ofthe contact-s bears a timed relation suc-hthat the breakingof the electric circuit by these contacts will occur at a through the. electric circuit is at or near a maximum and consequently a full; sparlr will be obtained between these" contacts for the purpose of exploding the fuel charge in the cylinder 31. in order to provide an additional Path for the lines of force between the poles oi the magneto 10 at the time the armature 15 is moved away from itsnormal. position, I provide an auxiliary armature, or keeper, l0 which is positioned near the polar extremities or" the magnet 10. This auxiliary armature is secured to a portion of the guide member 21 by a leaf spring Thelatter is riveted "to the end oi the armature do as indicated at a2 and is secured to the member 21 by any suitable means, as by the screws 43. The auxiliary armature 40 is composed of soft iron or other magnetic material and the spring ll may be composed of either magnetic or non-magnetic material. The spring a0 is very light as it need perform no function other than support he armature but it may also serve to press the free end of the armature d0 toward the adjacent portion of the magnet 10. The armature is, of course, drawn by the magnet 10 and't-his pull is sutilcie'nt' to draw it into engagement with the magnet irrespective of the tension 01": the spring ll. The free end of armature 40 is normally stopped by an arm 44.- which is pivoted to the outer face or the guide member 20.' The arm le is provided with a projection 46 which lies in the path of move ment or the armature bar 16 and bears against the latter when it is in attracted position. Normally the attracti n or" the armature 15 is such as to force the arm A outward against the auxiliary armature iOand hold it away from the'magnet 10. however; as the main armature bar 16 de scends, the. projection 16 on the at descends and said arm rotates about its pivot 45 by reason or" the magnetic pull exerted upon the auxiliary armature 40,- and the free end ofthe latter finally comes into engagement with the magnet 10. in this way a shunt for the lines of force of the magnetic circuit is provided. The purpose of the auxiliary keeper to, is to assist in maintaining the magnetism of the magnet 10.

This auxiliary keeper may not be necessary in all cases and where not needed said armature and the associated arm l may be omitted. A stop M limits the movement of arm I 44 in one direction and armature d0 restrains blows of the armature 15, the base 11 is provided with an rip-turned projection 47 which engages the curved portion of the magnet 10. This projection may not be necessary in all instances but it will obviously assist where only a single bolt 12 and bar 13 are used to hold the magnet 10 upon the base. Referring now to the high tension neto illustrated in Figs. 5 to 9 inclusive, it will be seen that the construction and arrangement ot the parts is the same in this form of the'invention as in the preceding, with certain exceptions. In the high tension machine the coil upon the armature 15, designated 50, includes a primary winding 51 and a. secondary winding 52. This coil, like the coil 49, is positioned between the blocks 17 and 18 of the armature structure. In this form of the invention, these blocks 17 and 18 are secured in place by pins 53 and 5% which have a driving lit in holes through the blocks and the bar 16. The high tension machine is also provided with a condenser 55 which is preferably secured to the base 11 by screws 56. It is also preferably located between the arms of the magnet 1O. In this form of the invention, the armature 15 and the adjacent guide member 20 carry electrical contacts 57 and 58. The contact 57 extends through a block 59 which is secured to the side of the member 20 by screws 60. This contact is suitably insulated from the block 59 by passing through a sleeve 61 of insulating material which separates it from the block 59. Locking nuts 62 and 63 serve to hold the contact firmly in place. Electrical contact may be made by attaching the conducting wire to the upper end of the contact 57. This may he done by soldering the wire to the end of the contact or by gripping it between the head 6% and the adjacent nut 65. The contact 58 is in the form of a plunger located in a socket- 65 in the armature bar 16. This contact has a reduced stem 66 which passes through an opening in the plate 67 secured to the under side of the bar 16 in any suitable way, as by screws, one of which, designated 68, is shown. A coiled compression spring 69 surrounds the stem 66 and bears against the plate 67 at one end and against a collar 66 on the contact 58 at the other end. The action of this spring is to normally push the contact 58 upward. By this means a yielding electrical connection is established between the contacts 5'? and 58 and the two are maintained in contact during the initial movement of the armature 15 away from magnet 10. As the armature 15 moves downward, however, a point is reached at which the contacts 5'? and 58 separate. This point is determined by the engagement of the collar 66 with a flange 67 formed at the upper end of the socket 65 in which contact 58 reciprocates. The closed position of all the parts is shown in full lines in Figs. 5 and 6 and the open position in dotted lines in Fig. 6 and in full lines in Fig. 7.

In this high tension machine the contacts 57 and 58 are ordinarily included in circuit with the. primary winding 51 of the coil 50. This is diagrammatically illustrated in Fig. 9. As there shown the circuit is completed by grounding the armature 15 and one terminal of the winding 51. The secondary winding 52 is connected in circuitwith the condenser 55 and the sparking contacts 7? and 71. These contacts, like contacts 30 and 32, are located in the engine cylinder but unlike them are separated by a permanent air gap which the high tension of the secondary circuit overcomes and thus produces spark. This action, of course, occurs when the armature 15 has been moved down by oscillating member 24. and the contacts 57 and 58 separated to break the primary circuit. Obviously, the circuit connection might be varied by connecting the condenser in series or in parallel with the spark terminals 70 and 71. Thus if switch 72 is left open and switch 7 is closed on its upper contact, the condenser will be connected in series. 911 the other hand, if switch 72 is closed and switch 7 3 is closed on its lower contact, the condenser will be connected in parallel.

In this form of he invention the keeper, or auxiliary armature, 40 might also be dispensed with if desired, the same as in the low tension machine, heretofore described. Likewise, the yoke 26 and spring 25 might be omitted. Again, the pivot pin 23 might be left out. All of these modifications and others not disclosed herein will be apparent to persons skilled in this art.

It may also be pointed out that in the low tension machine the timed relation between the initial movement of the bar 16 and the separation of the contacts is brought about by a yielding connection between two sections of the rod 33. These sections are connected by a telescopic oint having an enclosing sleeve 74 and an expanding spring 75. Normally the parts are extended as shown in Fig. 1. When so extended, a collar on the upper section engages a flange at the upper end of sleeve 74. lVhen bar 16 first engages rod 33 in its downward movement, the upper section of the latter is moved downward and spring 7 5 is compressed. Vihen the applied pressure over-comes the resistance of spring 34, then the lower section begins its downward movement. This continues until bar 16 has reached the limit of its downward movement. Upon the return of bar 16. rm

33 and its parts return to normal.

hat I claim as new and desire to secure by Letters Patent of the United States, is:

1. A magneto comprising a magnet. a main oscillating bar armature extending between the poles of said magnet, means for move it about its other end asa pivot, an electriccoil mounted on said armature and hav- 'ing windings adapted for inclusion in an ignition circuit, an auxiliary barvarmature yieldingly secured to one pole net, and means cooperating between said main and auxiliary armatures'to permit the free end of said auxiliary armature to approach the adjacent pole or said magnet as said main armature is moved away from its normal position.

2, A 'magneto comprising a magnet, a main oscillating bar armature extending between the poles or said magnet, means for actuating said main armature about a pivotal axis, an electric coil positioned in the magnetic field of said magnet and having windings adapted for inclusion in an ignition circuit, an auxiliary bar armature for said ma net, and means cooperating between said main and auxiliary armatures to permit said auxiliary armature to approach said magnet as said main armature is moved away from said magnet.

8. A magneto comprising a magnet having a polar face, a main oscillating armature having a face adapted to fit against said polar face, means for moving said armature about a pivotal axis to move sald armature face toward and from said polar face in a of said mag-v 1,4os.es9

ter face, anrelectric coil positioned in the held of said magnet and having'windings adapted for inclusion in an ignition ClfCult, an auxiliary armature' or said magnet, and

means whereby one armature recedes from said magnet as the other approaches it.

4. A magneto comprising a magnet, a main oscillating armature, an auxiliary armature, said armatures having their oscillating movements in different planes, means acting between said armatures whereby the movement of one of said armatures -is dependent upon the movement of the other,

and an electric COll positioned in the field of said magnet and having windings adapted;

for inclusion in an ignition circuit.

5. A magneto comprising a magnet, piv-- otally mounted main and auxiliary armatures, and a pivotally mounted stop device for holding said auxiliary armature away from said magnet except'when said main armature has receded from said magnet,

and an electric coil positioned in the field of said magnet and having windings adapted for inclusion inan ignition circuit.

In testimony whereof, I hereunto subscribe my name this 6th day of January, A. D. 1919. V

ALEXANDER H. HYNDMAN; 

